This invention relates to electric rotating machines and to a method of making the same.
The present invention, while of general application, is particularly well suited for use as a fractional horsepower motor. Motors having related electromagnetic characteristics but of different physical configuration are disclosed, for example, in A.W. Haydon U.S. Pat. Nos. 3,495,113 granted Feb. 10, 1970, 3,495,111 also granted Feb. 10, 1970, 3,564,214 granted Feb. 16, 1971, 3,909,646 granted Sept. 30, 1975, 4,004,168 granted Jan. 18, 1977 and 4,087,709 granted May 2, 1978. Such motors customarily utilize a two pole rotor and a plurality of salient stator poles arranged around the rotor to provide a nonuniform air gap therebetween. Certain of the stator poles are shaded, and this feature, together with the nonuniform air gap and the unique design of the rotor, results in a motor which begins rotating substantially instantaneously in response to the energization of the surrounding field coil.
Heretofore, difficulties were encountered in the manufacture of fractional horsepower motors and other electric rotating machines particularly on a mass production basis. As an illustration, the assembly of the machines was unnecessarily time consuming and often required complex tooling and excessive handling of the individual machine components. In addition, electric rotating machines of the type previously employed frequently were made from a comparatively large number of separate parts which each needed to be fabricated and fitted together in operable relationship with the remaining parts. Still further difficulties arose heretofore in cases in which weight limitations were placed on the machines, and in several instances the overall weight of the machine was excessive for the particular application.